OVCP:CSV
This is a Bosch Cold Start Valve feeding additional gas into the Over Valve Cover Pipe controlled by a pressure sensitive switch. When the switch is active it can open this valve when boost hits at least 15psi or is adjustable for a higher setting if wanted.
Many cars use one of these valves or a similar one to aid in cold engine start-up. One nice part about getting this valve today was I also found another 4G64 wide block and bought that for later. There are some different styles of these valves. We picked up one from a Toyota and instead of spraying straight out the tip it sprays two streams sideways. This was mounting with two stainless bolts and some rubber grommets and tapped out for a 1/8"npt elbow to we could add it into the line in front of the fuel pressure regulator. Reason begin, the 19C runs out of gas on the stock fuel system around 17psi so for that safer feeling and hopefully a couple more lbs. boost we have added this valve.
The hardest part was drilling out the threads that the valve had for the original banjo bolt to fit the 1/8" npt elbow. There isn't allot of depth to work with so the tap was turned down as far as possible then removed and 2 threads at a time were ground off until the tap was in completely so there was a good amount of threads catching for safety. A few threads might work, but that is full fuel pressure on that fitting so a good strong seal is a must. The two bolts were ground down, Lowes didn't sell a shorter one...
Drill the holes in the OVCP large enough so when you insert the valve and bolts they don't cut the grommets on the inside. When tightened down they seal the holes up.
Test fit the parts so you know everything will fit
New valves can run 60.00-200.00 and more depending on application, er where you buy them. lol, online maybe 45.00 or so sometimes, the junkyard was 10.00. Cleaned it all and a cost of Aluminum paint and looks just fine. The clip has a rubber seal, it was good as new in there so we grabbed that too.
Before the CSV, the 19C was running out of gas at high rpms @16psi, now with the valve activated it can run much safer and go up there at 20psi. Don't try this at home boys and girls, the valve does spray lots of fuel and if that somehow fell out of your OVCP you'd be in serious trouble. As with all fuel mods, be careful and always inspect your engine bay frequently for leaks or loose parts. A second valve could be added for even more boost, or a sprayer tip to inject a water/alcohol mixture.... more on that later.
We added an indicator light to glow so you can tell when the valve is open, it lights green and is next to the a/f gauge. It's visible from the corner of your eye so you can still watch the boost and more importantly -the road. It isn't illuminated now; the car is at idle.
ok, here's what the valve does when it's open using the test port on the fuel pump and the pressure switch jumpered....
mouse over to play or right click and save
You can't even tell when it opens up when driving, no surge or hiccup. It's tied into the RRFPR so this was spraying ~36psi of fuel, a few passes on the highway for setting the pressure switch then the base was raised to 40psi and boost set to 20psi. You could tell the difference. This was an inexpensive addition and anyone could benefit from.